CVE-2025-55158 | Vim double-free vulnerability during Vim9 script import operations

Vim is an open source, command line text editor. In versions from 9.1.1231 to before 9.1.1406, when processing nested tuples during Vim9 script import operations, an error during evaluation can trigger a double-free in Vim’s internal typed value (typval_T) management. Specifically, the clear_tv() function may attempt to free memory that has already been deallocated, due to improper lifetime handling in the handle_import / ex_import code paths. The vulnerability can only be triggered if a user explicitly opens and executes a specially crafted Vim script. This issue has been patched in version 9.1.1406.

Published: 2025-08-11 Last update: 2025-08-12 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2025-55158 is rated Moderate Risk (46.4/100): CVSS Medium severity, with medium exploitation likelihood (EPSS 0.29%). Mandatory action: Review affected assets and schedule remediation.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2025-55158

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-07 0.07% 0.29% +0.23%
2 2026-04-27 0.04% 0.07% +0.03%
3 2026-01-07 0.04%

Full EPSS history (5 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2025-55158

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
6.9 4.0 MEDIUM
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network.
Attack complexity (AC:L)
Exploitation conditions are straightforward and stable.
Attack requirements (AT:N)
No additional preconditions are required beyond normal reachability.
Privileges required (PR:N)
No privileges are required.
User interaction (UI:A)
User interaction is required in an active way.
Vulnerable system confidentiality impact (VC:N)
No confidentiality impact on the vulnerable system.
Vulnerable system integrity impact (VI:N)
No integrity impact on the vulnerable system.
Vulnerable system availability impact (VA:H)
High availability impact on the vulnerable system.
Subsequent system confidentiality impact (SC:N)
No confidentiality impact on subsequent systems.
Subsequent system integrity impact (SI:N)
No integrity impact on subsequent systems.
Subsequent system availability impact (SA:N)
No availability impact on subsequent systems.
Exploit maturity (threat) (E:X)
Not defined: no reliable threat intelligence; scoring assumes the worst case (equivalent to Attacked).
Confidentiality requirement (CR:X)
Not defined: insufficient information; scoring treats this like High (worst case).
Integrity requirement (IR:X)
Not defined: insufficient information; scoring treats this like High (worst case).
Availability requirement (AR:X)
Not defined: insufficient information; scoring treats this like High (worst case).
Modified attack vector (MAV:X)
Not defined: scoring uses the Base Attack Vector (AV).
Modified attack complexity (MAC:X)
Not defined: scoring uses the Base Attack Complexity (AC).
Modified attack requirements (MAT:X)
Not defined: scoring uses the Base Attack Requirements (AT).
Modified privileges required (MPR:X)
Not defined: scoring uses the Base Privileges Required (PR).
Modified user interaction (MUI:X)
Not defined: scoring uses the Base User Interaction (UI).
Modified vulnerable system confidentiality impact (MVC:X)
Not defined: scoring uses the Base VC metric.
Modified vulnerable system integrity impact (MVI:X)
Not defined: scoring uses the Base VI metric.
Modified vulnerable system availability impact (MVA:X)
Not defined: scoring uses the Base VA metric.
Modified subsequent system confidentiality impact (MSC:X)
Not defined: scoring uses the Base SC metric.
Modified subsequent system integrity impact (MSI:X)
Not defined: scoring uses the Base SI metric.
Modified subsequent system availability impact (MSA:X)
Not defined: scoring uses the Base SA metric.
Safety (supplemental) (S:X)
Not evaluated.
Automatable (supplemental) (AU:X)
Not evaluated.
Recovery (supplemental) (R:X)
Not evaluated.
Value density (supplemental) (V:X)
Not evaluated.
Vulnerability response effort (supplemental) (RE:X)
Not evaluated.
Provider urgency (supplemental) (U:X)
Not evaluated.
[email protected]
8.8 3.1 HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:R)
A real person has to do something—click, install, enable—otherwise it doesn’t land.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
2.8 5.9 [email protected]

Weakness enumeration for CVE-2025-55158

OS Trackers for CVE-2025-55158

vendor priority summary link
alpine medium CVE-2025-55158: 1 source package rows (vim); 2 state rows across 1 repos (edge-main); fixed 0, open 2. https://security.alpinelinux.org/vuln/CVE-2025-55158
debian unimportant CVE-2025-55158 unimportant priority: Debian including 1 source packages (vim), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5. https://security-tracker.debian.org/tracker/CVE-2025-55158
redhat low https://access.redhat.com/security/cve/CVE-2025-55158
suse medium CVE-2025-55158 severity moderate: SUSE including 292 source package names (13.2-9.33:libsystemd0-254.24-1.1, 13.2-9.33:libudev1-254.24-1.1, …), 889 product×package rows across 297 product lines (Container suse/manager/5.0/x86_64/server, Container suse/multi-linux-manager/5.1/x86_64/server, … (297 product lines)): Fixed 662, Known Affected 226, Known Not Affected 1. https://www.suse.com/security/cve/CVE-2025-55158/
ubuntu medium CVE-2025-55158 medium priority: Ubuntu including 1 source packages (vim), 8 status rows across 8 suites (bionic, focal, jammy, noble, plucky, trusty, upstream, xenial): not-affected 7, released 1. https://ubuntu.com/security/CVE-2025-55158

Affected software / configurations for CVE-2025-55158

Vendor Product Version Raw CPE
vim vim >= 9.1.1231, < 9.1.1406 cpe:2.3:a:vim:vim:*:*:*:*:*:*:*:*

References for CVE-2025-55158

cvelogic Threat Intelligence